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1.
J Inorg Biochem ; 259: 112663, 2024 Jul 14.
Article in English | MEDLINE | ID: mdl-39024775

ABSTRACT

Given the recognized major problem of microbial drug resistance for human health, new metal-based drugs have been currently explored for their antimicrobial properties, including gallium-based compounds as potential metallophores that could perturb Fe's interactions with proteins. Herein we have designed and synthesized two bis-kojate ligands (named L4 and L6) and studied their Ga(III) complexes for their physico-chemical and biological properties. In particular a detailed study of their complexation properties in aqueous solution, showed equilibrium models with formation of quite stable dinuclear 2:3 metal:ligand complexes, though with different stability. Solid state complexes were also prepared and characterized and complementary DFT studies indicated that [Ga2(L4)3] complex, with higher stability, seems to adopt a three-ligand bridging conformation, while that for L6 adopt a one ligand bridging conformation. Preliminary investigation of the antibacterial activity of these gallium complexes showed antipseudomonal activity, which appeared higher for the complex with L4, a feature of potential interest for the scientific community.

2.
Sci Rep ; 14(1): 14961, 2024 06 28.
Article in English | MEDLINE | ID: mdl-38942787

ABSTRACT

Methicillin-resistant Staphylococcus (MRS) has been associated with neonatal infections, with colonization of the anovaginal tract being the main source of vertical transmission. The COVID-19 pandemic has altered the frequency of antibiotic usage, potentially contributing to changes in the dynamics of bacterial agents colonizing humans. Here we determined MRS colonization rates among pregnant individuals attending a single maternity in Rio de Janeiro, Brazil before (January 2019-March 2020) and during (May 2020-March 2021) the COVID-19 pandemic. Anovaginal samples (n = 806 [521 samples before and 285 during the pandemic]) were streaked onto chromogenic media. Colonies were identified by MALDI-TOF MS. Detection of mecA gene and SCCmec typing were assessed by PCR and antimicrobial susceptibility testing was done according to CLSI guidelines. After the onset of the pandemic, MRS colonization rates increased significantly (p < 0.05) from 8.6% (45) to 54.7% (156). Overall, 215 (26.6%) MRS isolates were detected, of which S. haemolyticus was the most prevalent species (MRSH, 84.2%; 181 isolates). SCCmec type V was the most frequent among MRS (63.3%; 136), and 31.6% (68) of MRS strains had a non-typeable SCCmec, due to new combinations of ccr and mecA complexes. Among MRS strains, 41.9% (90) were resistant to at least 3 different classes of antimicrobial agents, and 60% (54) of them were S. haemolyticus harboring SCCmec V. MRS colonization rates and the emergence of multidrug-resistant variants detected in this study indicate the need for continuing surveillance of this important pathogen within maternal and child populations.


Subject(s)
COVID-19 , Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Humans , Female , Pregnancy , COVID-19/epidemiology , COVID-19/virology , Staphylococcal Infections/epidemiology , Staphylococcal Infections/microbiology , Methicillin-Resistant Staphylococcus aureus/genetics , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/drug effects , Adult , Brazil/epidemiology , Pregnancy Complications, Infectious/microbiology , Pregnancy Complications, Infectious/epidemiology , Anti-Bacterial Agents/pharmacology , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Microbial Sensitivity Tests , Pandemics , Vagina/microbiology
3.
Lett Appl Microbiol ; 75(2): 184-194, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35398923

ABSTRACT

Members of the genus Enterococcus are among the most relevant etiologic agents of bovine clinical and subclinical mastitis, a major problem for the dairy industry. In Brazil, clonal diversity, and multidrug resistance profiles related to bovine infections need further investigation. In this study, 11 bacterial strains recovered from mastitis subclinical cases detected in different farms of São Paulo, Brazil, were identified as Enterococcus faecalis (n = 8) and Enterococcus mundtii (n = 3) by biochemical testing and MALDI-TOF mass spectrometry. Pulsed-field gel electrophoresis categorized the enterococcal isolates into two main clusters (A and B) with similarity ranging from 85 to 100%. The isolates were shown to be resistant tetracycline (73%), erythromycin (73%), quinupristin-dalphopristin (64%), norfloxacin (9%), fosfomycin (9%) and linezolid (9%). Moreover, seven strains (64%) were considered multidrug-resistant. All the isolates were able to produce biofilms when grown in milk for 24 h: 54·54% were classified as moderate producers and 45·45% were weak producers. Interestingly, only two strains (Ef17 and Em42) remained as moderate biofilm producers after 48 h incubation. Moreover, all isolates showed no ability to form biofilm in tryptic soy broth (TSB) after 24 and 48 h incubation. In addition, cytoskeleton components were partially involved in E. faecalis and E. mundtii entry to epithelial cells as demonstrated by induction of actin stress fibre. In conclusion, enterococci isolates recovered from bovine subclinical mastitis were resistant to several classes of antibiotics, showing the ability to form biofilms in milk and invade mammary epithelial cells, suggesting an advantageous feature in mammary gland colonization during mastitis development. In addition, they can spread along the food chain by different routes and eventually constitute a possible threat for public health, including E. mundtii specie.


Subject(s)
Mastitis, Bovine , Animals , Anti-Bacterial Agents/pharmacology , Biofilms , Brazil/epidemiology , Cattle , Drug Resistance, Bacterial , Enterococcus , Enterococcus faecalis , Epithelial Cells , Female , Humans , Mastitis, Bovine/microbiology , Microbial Sensitivity Tests
4.
Animal ; 15(1): 100021, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33573936

ABSTRACT

Nucleotides are important to cell growth and division and are crucial to the rapid proliferation of such cells as the intestinal mucosa and immune cells. Accordingly, the nucleotide requirements of animals are high during periods of rapid growth and periods of stress like post-weaning period. Thus, nucleotide supplementation may be a possible alternative to in-feed antibiotics as growth promoter in this phase. The study aimed to evaluate dietary nucleotide supplementation as an alternative to in-feed antibiotics on performance and gut health of weaned piglets. Ninety-six 21-day-old piglets, weighing 7.44 ±â€¯0.65 kg, were allocated into 1 of 3 treatments (8 pens per treatment; 4 pigs per pen) in a 14-day trial. Dietary treatments consisted of control: corn-soybean meal-based diet; nucleotides: control +2 g/kg of a nutritional additive with purified nucleotides; and antibiotic: control +0.8 g/kg of antibiotic growth promoter based on colistin and tylosin. Performance variables and fecal score were not affected (P > 0.05) by supplementing nucleotide or antibiotic. Nucleotides treatment had similar effect to antibiotic and superior to control (P < 0.05) on enhancing duodenum villus height, jejunum crypt depth, and reduction of Paneth cellular area. Duodenum and ileum of animals supplemented with nucleotides or antibiotics had higher (P < 0.05) number of proliferating cells than did those of control animals, whereas the jejunum of animals that received antibiotic diets presented more (P < 0.05) proliferating cells than either the nucleotides or control animals. Jejunum of nucleotide-treated piglets showed a greater number of apoptotic cells than those fed antibiotic or control diets (P < 0.05). Nucleotides and antibiotic treatments decreased the B lymphocyte counts in duodenum and ileum (P < 0.05) but increased in the jejunum (P < 0.05), when compared to the control treatment. Relative abundance of mitogen-activated protein kinases-6, haptoglobin, and tumor necrosis factor-α mRNA was not influenced (P > 0.05) by treatments. In the ileal, antibiotic supplementation reduced total bacteria quantification compared to nucleotide supplementation or the control (P < 0.05), whereas nucleotides supplementation increased enterobacteria proliferation compared to the antibiotic or control diets (P < 0.05). However, nucleotides and antibiotic reduced (P < 0.05) colon total bacteria quantification when compared to control. These results suggest that the nucleotides source used to weaned piglets improved gut health by modulating the local immune response and modulating intestinal mucosa development, and, therefore, nucleotides may be an alternative to antibiotics as growth promoters.


Subject(s)
Animal Feed , Anti-Bacterial Agents , Animal Feed/analysis , Animals , Diet/veterinary , Dietary Supplements , Intestinal Mucosa , Nucleotides , Swine , Weaning
5.
Sci Adv ; 5(5): eaaw1317, 2019 05.
Article in English | MEDLINE | ID: mdl-31131324

ABSTRACT

Awareness that traditional two-dimensional (2D) in vitro and nonrepresentative animal models may not completely emulate the 3D hierarchical complexity of tissues and organs is on the rise. Therefore, posterior translation into successful clinical application is compromised. To address this dearth, on-chip biomimetic microenvironments powered by microfluidic technologies are being developed to better capture the complexity of in vivo pathophysiology. Here, we describe a "tumor-on-a-chip" model for assessment of precision nanomedicine delivery on which we validate the efficacy of drug-loaded nanoparticles in a gradient fashion. The model validation was performed by viability studies integrated with live imaging to confirm the dose-response effect of cells exposed to the CMCht/PAMAM nanoparticle gradient. This platform also enables the analysis at the gene expression level, where a down-regulation of all the studied genes (MMP-1, Caspase-3, and Ki-67) was observed. This tumor-on-chip model represents an important development in the use of precision nanomedicine toward personalized treatment.


Subject(s)
Colorectal Neoplasms/diagnosis , Lab-On-A-Chip Devices , Nanomedicine/methods , Precision Medicine/methods , Biomimetics , Caspase 3/metabolism , Cell Line, Tumor , Cell Survival , Coculture Techniques , Colorectal Neoplasms/metabolism , Dendrimers/chemistry , Gene Expression Regulation, Neoplastic , HCT116 Cells , Humans , Imaging, Three-Dimensional , Ki-67 Antigen/metabolism , Matrix Metalloproteinase 1/metabolism , Microfluidics , Nanoparticles/chemistry
6.
J Endocrinol Invest ; 41(5): 523-529, 2018 May.
Article in English | MEDLINE | ID: mdl-28929353

ABSTRACT

BACKGROUND: Autoimmune thyroid disease (ATD) patients may have a higher prevalence of anti-parietal cell antibodies (APCA) than normal population. OBJECTIVE: To study the prevalence of APCA in a cohort of ATD patients to know its association with patient's clinical profile and gastrointestinal complaints. METHODS: APCA was sought for by indirect immunofluorescence test in 243 ATD patients: 136 (55.9%) with Graves' disease and 107 (44.0%) with Hashimoto's thyroiditis. A structured questionnaire for gastrointestinal symptoms, previous history of thrombosis, arthralgia and other autoimmune diseases in the patients and their families was applied. Positive and negative APCA individuals were compared. Positive patients were invited to perform upper gastrointestinal endoscopy and biopsy of duodenum segments. Sera from 100 healthy individuals from the same geographic area were used as controls. RESULTS: APCA was present in 20.1% (49/243) of ATD patients: 21.3% (29/136) in the Graves' sample and 18.6% (20/107) in the Hashimoto's sample (p = 0.61). Patients with positive APCA had more anemia (p = 0.03; OR = 2.89; 95% CI = 1.03-8.07) and less heartburn (p = 0.01; OR = 0.4; 95% CI = 0.20-0.83). Among the group of 49 APCA-positive patients, 24 agreed with upper endoscopy and it was found that 54.1% had atrophic gastritis. CONCLUSIONS: There is a high prevalence of positive APCA in ATD patients. APCA are more common in those with anemia and less common in those with complaints of heartburn. Almost half of positive APCA patients had atrophic gastritis.


Subject(s)
Autoantibodies/blood , Autoimmune Diseases/immunology , Hashimoto Disease/immunology , Parietal Cells, Gastric/immunology , Adult , Autoimmune Diseases/blood , Cross-Sectional Studies , Female , Follow-Up Studies , Hashimoto Disease/blood , Humans , Male , Prognosis
7.
Epidemiol Infect ; 145(8): 1720-1726, 2017 06.
Article in English | MEDLINE | ID: mdl-28264733

ABSTRACT

We performed two different approaches (broth enrichment step prior to culture (BEC) and PCR (BEPCR)) for detecting Streptococcus pneumoniae from nasopharyngeal specimens collected from 242 children aged <6 years attending one hospital (n = 140) and one childcare centre (n = 102) in a major urban area in Brazil. These specimens were collected immediately before the introduction of the 10-valent pneumococcal conjugate vaccine (PCV10) and the 13-valent vaccine (PCV13) for routine use in Brazil. Results were compared with previous findings obtained with direct culture (DC) on a selective medium. Colonisation prevalence was 58·3% (n = 141), being higher among children attending the childcare centre (62·7% vs. 55%). The culture-based methods (DC and BEC) enabled the detection of S. pneumoniae in 119 (49·2%) and 115 (47·5%) children, respectively. The PCR-based method (BEPCR) was more sensitive and 137 (56·6%) carriers were identified. Twenty-six serogroups/serotypes were identified, predominantly 6B, 19F, 14, 6A, 15C and 23F. Multiple colonisation was observed in 13 (5·4%) children. The estimated serotypes coverage of available PCVs was 40·4% for the 10-valent (included in the Brazilian immunisation programme) and 55·8% for the 13-valent (only available in private clinics). The use of robust approaches to obtain a more realistic insight about the asymptomatic carrier status is of paramount importance to estimate and assess the impact of vaccine implementation. The combination between culture-based and molecular methods constitutes a suitable strategy.


Subject(s)
Carrier State , Colony Count, Microbial , Nasopharynx/microbiology , Pneumococcal Infections/epidemiology , Pneumococcal Infections/microbiology , Polymerase Chain Reaction , Streptococcus pneumoniae/physiology , Brazil/epidemiology , Carrier State/epidemiology , Carrier State/microbiology , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Pneumococcal Vaccines/administration & dosage
8.
Neuroscience ; 317: 149-61, 2016 Mar 11.
Article in English | MEDLINE | ID: mdl-26791522

ABSTRACT

Streptococcus pneumoniae is the causative agent of numerous diseases including severe invasive infections such as bacteremia and meningitis. It has been previously shown that strains of S. pneumoniae that are unable to survive in the bloodstream may colonize the CNS. However, information on cellular components and pathways involved in the neurotropism of these strains is still scarce. The olfactory system is a specialized tissue in which olfactory receptor neurons (ORNs) are interfacing with the external environment through several microvilli. Olfactory ensheathing cells (OECs) which also form the glial limiting membrane at the surface of the olfactory bulb (OB) are the only cells that ensheathe the ORNs axons. Since previous data from our group showed that OECs may harbor S. pneumoniae, we decided to test whether infection of the OB or OEC cultures modulates the expression levels of neurotrophic factor's mRNA and its putative effects on the activation and viability of microglia. We observed that neurotrophin-3 (NT-3) and glial cell-line-derived neurotrophic factor (GDNF) expression was significantly higher in the OB from uninfected mice than in infected mice. A similar result was observed when we infected OEC cultures. Brain-derived neurotrophic factor (BNDF) expression was significantly lower in the OB from infected mice than in uninfected mice. In contrast, in vitro infection of OECs resulted in a significant increase of BDNF mRNA expression. An upregulation of high-mobility group box 1 (HMGB1) expression was observed in both OB and OEC cultures infected with S. pneumoniae. Moreover, we found that conditioned medium from infected OEC cultures induced the expression of the pro-apoptotic protein cleaved-caspase-3 and an apparently continuous nuclear factor-kappa B (NF-κB) p65 activation in the N13 microglia. Altogether, our data suggest the possible existence of an OEC-pathogen molecular interface, through which the OECs could interfere on the activation and viability of microglia, favoring the access of non-hematogenous S. pneumoniae strains to the CNS in the absence of bacteremia.


Subject(s)
Nerve Growth Factors/metabolism , Neuroglia/metabolism , Olfactory Bulb/metabolism , Olfactory Bulb/pathology , Pneumococcal Infections/pathology , 2',3'-Cyclic-Nucleotide Phosphodiesterases/metabolism , Actins/metabolism , Animals , Caspase 3/metabolism , Cells, Cultured , Disease Models, Animal , Gene Expression Regulation, Bacterial/physiology , HMGB1 Protein/genetics , HMGB1 Protein/metabolism , Male , Mice , Mice, Inbred BALB C , Models, Biological , N-Acetylmuramoyl-L-alanine Amidase/genetics , N-Acetylmuramoyl-L-alanine Amidase/metabolism , NF-kappa B/metabolism , Nerve Growth Factors/genetics , Neuroglia/microbiology , RNA, Messenger/metabolism
9.
Transplant Proc ; 42(2): 483-5, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20304171

ABSTRACT

BACKGROUND: Urinary tract infection (UTI) is the most common infectious complication after renal transplantation. Most infections are caused by uropathogenic Escherichia coli (UPEC). There are limited data on the prevalence of virulence traits among UPEC isolated from renal transplant recipients. This study compared the phenotypic and genotypic profiles of UPEC strains isolated from recipients with those from control patients. METHODS: E coli isolates that caused UTI in recipients versus nonimmunosuppressed control patients were characterized according to phylogenetic group and the presence of urovirulence genes pap1/pap2; sfa1/sfa2; afa1/afa2; aer1/aer2; and cnf1/cnf2. RESULTS: Thirty-six UPEC isolates from recipients and another 27 from control individuals were included in the study. The proportion of episodes of pyelonephritis in recipients (50%) versus control subjects (41%) was similar (P = .46). However, secondary bacteremia was observed only among recipients (n = 8; P < .001). There was no significant difference in the distribution of phylogenetic groups or the prevalence of analyzed virulence traits between UPEC isolated from the 2 groups. Nevertheless, strains associated with secondary bacteremia in recipients showed a higher prevalence of mannose-resistant hemagglutination (P = .013). CONCLUSION: The phenotypic and genotypic characteristics of UPEC isolated from recipients were similar to those from control patients at a tertiary care center. Secondary bacteremia in recipients was associated with a higher prevalence of mannose-resistant hemagglutination.


Subject(s)
Escherichia coli Infections/epidemiology , Kidney Transplantation/adverse effects , Urinary Tract Infections/epidemiology , Uropathogenic Escherichia coli/isolation & purification , Animals , Escherichia coli Infections/genetics , Female , Genotype , Goats , Guinea Pigs , Hemagglutination Inhibition Tests , Humans , Male , Medical History Taking , Pancreatitis-Associated Proteins , Phenotype , Pyelonephritis/epidemiology , Pyelonephritis/microbiology , Rabbits , Retrospective Studies , Sheep , Urinary Tract Infections/genetics , Urinary Tract Infections/microbiology , Urine/microbiology , Uropathogenic Escherichia coli/pathogenicity
10.
J Dairy Sci ; 93(1): 93-104, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20059908

ABSTRACT

The objective of this study was to isolate bacteriophages from environmental samples of 2 large commercial dairy farms using Escherichia coli isolated from the uteri of postpartum Holstein dairy cows as hosts. A total of 11 bacteriophage preparations were isolated from manure systems of commercial dairy farms and characterized for in vitro antimicrobial activity. In addition, a total of 57 E. coli uterine isolates from 5 dairy cows were phylogenetically grouped by triplex PCR. Each E. coli bacterial host from the uterus was inoculated with their respective bacteriophage preparation at several different multiplicities of infections (MOI) to determine minimum inhibitory MOI. The effect of a single dose (MOI=10(2)) of bacteriophage on the growth curve of all 57 E. coli isolates was assessed using a microplate technique. Furthermore, genetic diversity within and between the different bacteriophage preparations was assessed by bacteriophage purification followed by DNA extraction, restriction, and agarose gel electrophoresis. Phylogenetic grouping based on triplex PCR showed that all isolates of E. coli belonged to phylogroup B1. Bacterial growth was completely inhibited at considerably low MOI, and the effect of a single dose (MOI=10(2)) of bacteriophage preparations on the growth curve of all 57 E. coli isolates showed that all bacteriophage preparations significantly decreased the growth rate of the isolates. Bacteriophage preparation 1230-10 had the greatest antimicrobial activity and completely inhibited the growth of 71.7% (n=57) of the isolates. The combined action of bacteriophage preparations 1230-10, 6375-10, 2540-4, and 6547-2, each at MOI=10(2), had the broadest spectrum of action and completely inhibited the growth (final optical density at 600 nm

Subject(s)
Bacteriophages/physiology , Cattle Diseases/microbiology , Escherichia coli Infections/microbiology , Escherichia coli/virology , Uterus/microbiology , Animals , Bacteriophages/classification , Cattle , Dairying , Environmental Microbiology , Escherichia coli/classification , Escherichia coli/growth & development , Escherichia coli/isolation & purification , Female , Genetic Variation , Manure/virology , Phylogeny , Postpartum Period
11.
J Dairy Sci ; 93(1): 105-14, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20059909

ABSTRACT

The use of pathogenic-specific antimicrobials, as proposed by bacteriophage therapy, is expected to reduce the incidence of resistance development. Eighty Escherichia coli isolated from uteri of Holstein dairy cows were phenotypically characterized for antimicrobial resistance to ampicillin, ceftiofur, chloramphenicol, florfenicol, spectinomycin, streptomycin, and tetracycline by broth microdilution method. The lytic activity of a bacteriophage cocktail against all isolates was performed by a similar method. Additionally, the effect of different concentrations of antimicrobials and multiplicities of infections (MOI) of the bacteriophage cocktail on E. coli growth curve was measured. Isolates exhibited resistance to ampicillin (33.7%), ceftiofur (1.2%), chloramphenicol (100%), and florfenicol (100%). All strains were resistant to at least 2 of the antimicrobial agents tested; multidrug resistance (>or=3 of 7 antimicrobials tested) was observed in 35% of E. coli isolates. The major multidrug resistance profile was found for ampicillin-chloramphenicol-florfenicol, which was observed in more than 96.4% of the multidrug-resistant isolates. The bacteriophage cocktail preparation showed strong antimicrobial activity against multidrug-resistant E. coli. Multiplicity of infection as low as 10(-4) affected the growth of the E. coli isolates. The ratio of 10 bacteriophage particles per bacterial cell (MOI=10(1)) was efficient in inhibiting at least 50% of all isolates. Higher MOI should be tested in future in vitro studies to establish ratios that completely inhibit bacterial growth during longer periods. All isolates resistant to florfenicol were resistant to chloramphenicol and, because florfenicol was recently introduced into veterinary clinics, this finding suggests that the selection pressure of chloramphenicol, as well as other antimicrobials, may still play a relevant role in the emergence and dissemination of florfenicol resistance in E. coli. The bacteriophage cocktail had a notable capacity to inhibit the in vitro growth of E. coli isolates, and it may be an attractive alternative to conventional treatment of metritis by reducing E. coli in uteri of postpartum dairy cows.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteriophages/physiology , Cattle Diseases/microbiology , Escherichia coli Infections/veterinary , Escherichia coli/drug effects , Escherichia coli/virology , Uterus/microbiology , Animals , Cattle , Dairying , Drug Resistance, Microbial , Escherichia coli/classification , Escherichia coli/genetics , Escherichia coli/isolation & purification , Escherichia coli Infections/virology , Female , Microbial Sensitivity Tests , Postpartum Period
12.
Res Vet Sci ; 88(2): 214-7, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19765787

ABSTRACT

To compare the genotypes of Campylobacter jejuni and Campylobacter coli isolates of human and animal origin collected in Rio de Janeiro City, 30 C. jejuni and 35 C. coli isolates from animal sources (n=45) and human patients with gastroenteritis (n=20) were genotyped by PCR-based techniques, namely random amplified polymorphic DNA (RAPD-PCR) and enterobacterial repetitive intergenic consensus sequence (ERIC-PCR). RAPD-PCR identified 50 types and ERIC-PCR identified 22 genotypes, among the 65 Campylobacter isolates. Both PCR methods discriminated the C. jejuni and C. coli groups of isolates. Combining the results of both methods, no single genotype was shared between isolates from human and animal sources. Two groups of two C. coli isolates each with identical genotypes were found among poultry and pig isolates. A high level of genetic diversity observed among the Campylobacter isolates suggests lack of overlap between isolates from different sources.


Subject(s)
Campylobacter Infections/microbiology , Campylobacter coli/genetics , Campylobacter jejuni/genetics , Genetic Variation , Genotype , Animals , Brazil/epidemiology , Campylobacter Infections/epidemiology , Gastroenteritis/veterinary , Humans , Phylogeny
13.
Mem Inst Oswaldo Cruz ; 104(7): 1003-8, 2009 Nov.
Article in English | MEDLINE | ID: mdl-20027468

ABSTRACT

Restriction fragment length polymorphism (RFLP) analysis of a PCR-amplified fragment of the 16S rRNA gene was performed on reference strains belonging to 21 different enterococcal species and on 75 Enterococcus isolates recovered from poultry meat, pasteurised milk and fresh cheese. PCR amplification generated a 275 bp fragment, which was digested with three restriction endonucleases (DdeI, HaeIII, HinfI). The strains were divided into five groups (groups A-E) on the basis of their restriction patterns. Five biochemical tests (arabinose, arginine, manitol, methyl-beta-D-glucopyranoside and raffinose) were then performed in addition to RFLP analysis to narrow the identification of enterococcal strains to the species level. PCR-RFLP, in conjunction with the selected biochemical tests, allowed the precise identification of the 21 species of Enterococcus included in the present study. This proposed method is relatively simple and rapid and can be useful as an adjunct tool for accurate identification of Enterococcus.


Subject(s)
DNA, Bacterial/genetics , Enterococcus/genetics , Polymorphism, Restriction Fragment Length/genetics , RNA, Ribosomal, 16S/genetics , Animals , Base Sequence , DNA Restriction Enzymes , Enterococcus/classification , Enterococcus/isolation & purification , Food Microbiology , Polymerase Chain Reaction
14.
Microbiol Res ; 163(2): 225-33, 2008.
Article in English | MEDLINE | ID: mdl-16815695

ABSTRACT

The study was undertaken to determine the clonal relationship and the genetic diversity among Escherichia coli isolates by comparing a non-motile O157 variant with three O157:H7 EHEC isolates and one O55:H7 enteropathogenic E. coli (EPEC) strain. E. coli strains were characterized by sorbitol phenotype, multilocus enzyme electrophoresis, pulsed-field gel electrophoresis, random amplification polymorphic DNA, and the presence of specific virulence genes (stx, E-hly and LEE genes). Sorbitol fermentation was observed in O157:H- (strain 116I), O55:H7 and O157:H7 (strain GC148) serotypes. stx1 or stx2 and E-hly genes were only detected among O157:H7 isolates. LEE typing revealed specific allele distribution: eaegamma, tirgamma, espAgamma, espBgamma associated with EPEC O55:H7 and EHEC O157:H7 strains (B1/1 and EDL 933), eaealpha, tiralpha, espAalpha, espBalpha related to the 116I O157:H- strain and the GC148 strain presented non-typable LEE sequences. Multilocus enzyme profiles revealed two main clusters associated with specific LEE pathotypes. E. coli strains were discriminated by random amplification of polymorphic DNA-polymerase chain reaction and pulsed-field gel electrophoresis methodologies. The molecular approaches used in this study allowed the determination of the genetic relatedness among E. coli strains as well as the detection of lineage specific group markers.


Subject(s)
Enteropathogenic Escherichia coli/classification , Enteropathogenic Escherichia coli/genetics , Escherichia coli O157/classification , Escherichia coli O157/genetics , Animals , Bacterial Typing Techniques , Cattle , Cell Line , DNA Fingerprinting , DNA, Bacterial/genetics , Electrophoresis, Gel, Pulsed-Field , Enteropathogenic Escherichia coli/enzymology , Escherichia coli Infections/microbiology , Escherichia coli Infections/veterinary , Escherichia coli O157/enzymology , Fermentation , Humans , Random Amplified Polymorphic DNA Technique , Sorbitol/metabolism , Virulence Factors/genetics
15.
Braz. j. phys. ther. (Impr.) ; 10(4): 407-411, out.-dez. 2006.
Article in Portuguese | LILACS | ID: lil-448252

ABSTRACT

INTRODUÇÃO: A medida da amplitude do movimento (ADM) é um importante parâmetro utilizado na avaliação e no acompanhamento fisioterapêutico, conseqüentemente, a confiabilidade dessa medida e dos instrumentos utilizados devem ser avaliados. OBJETIVOS: O objetivo deste estudo foi avaliar a confiabilidade das medidas intra-examinador e interexaminador da ADM ativa de dorsiflexão do tornozelo, por meio da goniometria e de forma mais funcional em cadeia cinética fechada (CCF). MATERIAIS E MÉTODOS: Dois examinadores realizaram, em dois dias de teste, as mensurações de ambos os membros de 22 sujeitos saudáveis. A ADM ativa de dorsiflexão foi medida primeiro com o sujeito em prono, utilizando o goniômetro universal e, posteriormente, com o sujeito em dorsiflexão, na posição ortostática com o pé testado sobre uma fita métrica. O coeficiente de correlação intraclasse (CCI) foi utilizado para a análise da confiabilidade das medidas, e o teste t pareado e independente foi utilizado para verificar a diferença entre as médias de dois dias de teste e entre os dois examinadores, respectivamente. RESULTADOS: Os coeficientes de correlação intraclasse (CCI) demonstraram de baixa a moderada confiabilidade intra-examinador, com CCI: 0,32 a 0,72, e moderada confiabilidade interexaminador, com CCI de 0,57 e 0,66 para a goniometria. Para a medida em CCF a confiabilidade foi alta tanto para a condição intra-examinador (CCI de 0,93 e 0,96 para os tornozelos direito e esquerdo, respectivamente) quanto para interexaminador (CCI de 0,98 e 0,99 para os tornozelos direito e esquerdo, respectivamente). CONCLUSÃO: Esses resultados indicaram que a confiabilidade da avaliação em CCF é maior que a do goniômetro universal, e isso indica ser um método confiável para sua aplicação clínica ao envolver o mesmo ou diferentes avaliadores.


BACKGROUND: Range of motion (ROM) measurements are an important parameter for physiotherapeutic assessment and follow-up. Consequently, the reliability of such measurements and the instruments utilized must be evaluated. OBJETIVE: To evaluate the intrarater and interrater reliability of active ROM measurements for ankle dorsiflexion using a goniometer and the more functional method of closed kinetic chains (CKC). METHOD: Two examiners measured both ankles of 22 healthy subjects, on two test days. The active ROM for dorsiflexion was first measured with the subject in the prone position using a universal goniometer and subsequently with the subject in the orthostatic position, with the foot to be tested in dorsiflexion on a measuring tape. The intraclass correlation coefficient (ICC) was used to analyze the reliability of the measurements, and Student's t test for paired and independent samples was used to investigate differences between the means for the two test days and between the two examiners, respectively. RESULTS: The ICC showed low to moderate intrarater reliability (ICC: 0.32-0.72) and moderate interrater reliability (ICC: 0.57-0.66) for the goniometer measurements. For the CKC measurements, both intrarater reliability and interrater reliability were high: intrarater ICC of 0.93 and 0.96 for the right and left ankles, respectively; interrater ICC of 0.98 and 0.99 for the right and left ankles, respectively. CONCLUSION: These results indicated that the reliability of the CKC evaluation was greater than the reliability of the universal goniometer. This shows that CKC is a reliable method for clinical application involving the same or different examiners.

17.
J Dairy Sci ; 88(9): 3211-9, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16107411

ABSTRACT

Phenotypic characteristics, antimicrobial susceptibility, and genetic relationships were analyzed in 107 Staphylococcus aureus isolates recovered from cows with subclinical mastitis in Southeastern Brazil. Thirteen different biochemical patterns were detected among isolates. A predominant pattern represented by about 54% of the isolates was distributed among several herds. Isolates of distinct phenotypic profiles were also detected within a herd. Susceptibility to ampicillin, cefotaxime, cephalotin, chloramphenicol, erythromycin, gentamycin, kanamycin, nitrofurantoin, norfloxacin, ofloxacin, oxacillin, penicillin, rifampin, sulfamethoxazole-trimethoprim, tetracycline, trimethoprim, and vancomycin, determined by the disk diffusion method, was observed in 44.9% of isolates. On the other hand, 55.1, 7.4, and 2.8% of the strains were resistant to ampicillin/penicillin, tetracycline, and erythromycin, respectively. Genetic diversity was analyzed by pulsed-field gel electrophoresis using SmaI as the restriction enzyme. All isolates could be typed by pulsed-field gel electrophoresis, which identified 16 types and 24 subtypes. Type A and its subtypes comprised 54.2% of all isolates and were recovered from 6 of the 9 herds analyzed. Other types and subtypes were also found in multiple herds. Although multiple types and subtypes were found within a specific herd, a predominant type was frequently observed.


Subject(s)
Drug Resistance, Bacterial , Mastitis, Bovine/microbiology , Staphylococcus aureus/isolation & purification , Staphylococcus aureus/metabolism , Animals , Brazil , Cattle , Electrophoresis, Gel, Pulsed-Field , Female , Fermentation , Genetic Variation , Genotype , Mastitis, Bovine/drug therapy , Microbial Sensitivity Tests , Milk/microbiology , Phenotype , Staphylococcus aureus/genetics
18.
Vet Microbiol ; 109(1-2): 75-81, 2005 Aug 10.
Article in English | MEDLINE | ID: mdl-15963664

ABSTRACT

An active chloramphenicol efflux system was demonstrated in a multiresistant E. coli isolated from poultry carcass. The effect of different concentrations of chloramphenicol on the original strain and on the plasmid-cured strain was determined in the presence and in the absence of CCCP, an uncoupler of the proton-motive force. Minimal inhibitory concentration (MIC) was lower in the presence of CCCP in the original strain. The plasmid-cured strain displayed lower resistance for chloramphenicol than the wild type, but the MIC was not affected by CCCP. The combined results indicate a plasmid encoded energy dependent resistance mechanism. 3H-chloramphenicol accumulation within the cells was measured by scintillation counting. The uptake or the efflux of 3H-chloramphenicol was influenced by CCCP in the original strain, but not in the plasmid-cured strain. More than one chloramphenicol resistance mechanism may exist in this strain. E. coli is an important commensal or pathogen that inhabits the gastrointestinal tracts of humans and animals, so a plasmid encoded active drug resistance mechanism can be a potential source of horizontal transfer of resistance.


Subject(s)
Anti-Bacterial Agents/pharmacokinetics , Chloramphenicol Resistance/physiology , Chloramphenicol/pharmacokinetics , Escherichia coli Infections/veterinary , Escherichia coli/metabolism , Poultry Diseases/microbiology , Animals , Anti-Bacterial Agents/antagonists & inhibitors , Anti-Bacterial Agents/pharmacology , Carbonyl Cyanide m-Chlorophenyl Hydrazone/analogs & derivatives , Carbonyl Cyanide m-Chlorophenyl Hydrazone/pharmacology , Chloramphenicol/antagonists & inhibitors , Chloramphenicol/pharmacology , Drug Resistance, Multiple, Bacterial , Escherichia coli/drug effects , Escherichia coli/isolation & purification , Escherichia coli Infections/microbiology , Ionophores/pharmacology , Microbial Sensitivity Tests , Plasmids , Poultry , Proton-Motive Force/drug effects
19.
J Hosp Infect ; 60(1): 51-5, 2005 May.
Article in English | MEDLINE | ID: mdl-15823657

ABSTRACT

Ralstonia pickettii and Burkholderia cepacia complex isolates are causes of healthcare-associated infection related to contamination of intravenously administered products. Based on microbiological and epidemiological data and molecular typing by pulsed-field gel electrophoresis, we report the occurrence of two outbreaks of R. pickettii and B. cepacia complex bloodstream infections. The first outbreak occurred from August 1995 to September 1996, and the second outbreak occurred from 28 March to 8 April 1998, affecting adults and neonates, respectively. Infusion of contaminated water for injection was the source of infection.


Subject(s)
Bacteremia/etiology , Burkholderia Infections/etiology , Burkholderia cepacia complex , Cross Infection/etiology , Drug Contamination , Gram-Negative Bacterial Infections/etiology , Injections/adverse effects , Ralstonia , Water Microbiology , Adult , Bacteremia/epidemiology , Brazil/epidemiology , Burkholderia Infections/epidemiology , Burkholderia cepacia complex/classification , Burkholderia cepacia complex/genetics , Burkholderia cepacia complex/isolation & purification , Cross Infection/epidemiology , DNA, Bacterial/analysis , DNA, Bacterial/genetics , Disease Outbreaks/statistics & numerical data , Electrophoresis, Gel, Pulsed-Field , Fatal Outcome , Female , Genotype , Gram-Negative Bacterial Infections/epidemiology , Humans , Infant, Newborn , Infection Control , Male , Molecular Epidemiology , Phylogeny , Ralstonia/classification , Ralstonia/genetics , Ralstonia/isolation & purification , Seasons
20.
J Hosp Infect ; 59(1): 19-26, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15571849

ABSTRACT

Studies on the genetic diversity of oxacillin-resistant coagulase-negative staphylococcal (CNS) isolates are important for the control and prevention of infections. The present study evaluated the clonal diversity of oxacillin-resistant Staphylococcus epidermidis (ORSE) and Staphylococcus haemolyticus (ORSH) strains, isolated from patients in nine Brazilian medical centres by using pulsed-field gel electrophoresis (PFGE) after digestion of bacterial DNA using SmaI. PFGE analysis of ORSE (N=44) and ORSH (N=25) strains showed the presence of 29 restriction profiles clustered in 16 PFGE types, and 21 distinct profiles in 15 PFGE types, respectively, indicating a large genetic diversity among isolates of both of these species. Among the ORSE isolates, 23 (52%) strains belonged to two predominant PFGE types (named A and B), which were observed in most of the hospitals assessed, indicating the spread of these PFGE types in hospitals located in Rio de Janeiro. The spread of PFGE types of ORSH was also detected in some of the hospitals investigated. The results show that PFGE is a suitable tool for epidemiological studies of oxacillin-resistant CNS, and can be used as a basis for infection control procedures for these multiresistant organisms.


Subject(s)
Cross Infection/microbiology , Electrophoresis, Gel, Pulsed-Field/methods , Genome, Bacterial , Oxacillin , Staphylococcal Infections/microbiology , Staphylococcus epidermidis/genetics , Staphylococcus haemolyticus/genetics , Bacterial Proteins/genetics , Brazil/epidemiology , Cluster Analysis , Cross Infection/epidemiology , Cross Infection/prevention & control , Cross Infection/transmission , Drug Resistance, Bacterial/genetics , Electrophoresis, Gel, Pulsed-Field/standards , Epidemiologic Studies , Genetic Variation/genetics , Hospitals, Teaching , Hospitals, Urban , Humans , Infection Control , Microbial Sensitivity Tests , Molecular Epidemiology , Phylogeny , Polymerase Chain Reaction/methods , Prevalence , Restriction Mapping , Staphylococcal Infections/epidemiology , Staphylococcal Infections/prevention & control , Staphylococcal Infections/transmission , Staphylococcus epidermidis/isolation & purification , Staphylococcus haemolyticus/isolation & purification
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